Turning

Subject:

Hunter tool sharpness

john lucasI'm still doing testing for my article on how different steels sharpen. Took a Hunter carbide cutter to the college to be photographed under the Scanning Electron microscope. John K Jordan was also nice enough to loan me a BESS sharpness tester. Been having fun with that. Anyway back to the carbide cutter. On the BESS tester it test as sharp as high end cutlery right out of the box. No wonder it cuts so well. It's not as sharp as the other tools I hand sharpened and stropped but those came out sharper than Utility knife razors but not quite up to a single edge razor. Just for fun I took a Thompson spindle gouge sharpened at a 45 degree included angle on a 180 CBN and then honed with a 600 grit diamond hone on the inside and outside of the flute. The Hunter cutter was quite a bit sharper than this gouge tested.
Under the SCM the edge is really unique. It looked prefectly straight up to about 1000X magnification which is really sharp. When we went higher it had a series of large convex waves for lack of a better description. These waves then had irregular saw teeth like the other tools do when approaching this magnification.
It wasn't as sharp as the other tools but is quite a bit sharper right out of the box than most of you sharpen your own tools. Very interesting. I'll post photos after I get the article written which will go in More Woodturning online magazine